Category Archives: Subaru

This is a project that you don’t see every day. A customer brought us a Factory Five 818 kit car. It was running a completely stock WRX motor and 5-speed with a Megasquirt MS3Pro controlling everything.

We ended up tossing on a very lightly 2017 STi turbo and intercooler to make this thing even more fun. It currently doesn’t have its body, but it’s definitely cool to see all of the inner workings of the suspension and frame.

We’re going to get this over to the dyno for some tuning action. With the weight of this car just touching 2,000 pounds, I can’t imagine how much fun it’ll be to drive. I’m thinking this will end up around the 300whp mark. Possibly more since it’s now rear-wheel drive instead of all-wheel drive. Once it’s all tuned up the owner is going to put the body on it and bring it back for a custom exhaust. I can’t wait to see it once it’s all buttoned up.

Both are 2017 STi’s, but the one on the right is getting the PSI built turbo kit. It’s pretty awesome when a customer brings in a practically brand new car for a cool build. The engine is being left stock… for now, but it’s getting the turbo treatment with a big ole Precision turbo.

The plan is to have all the intercooler piping powder coated wrinkle black, and the header & up-pipe ceramic coated by JT Coating. It’ll have a nice clean look, especially with the shaved and powder coated intake manifold. This setup will be pushing it for a stock motor, but I foresee this car getting a built engine in the near future. Here’s a few pics of the fabrication process.

Some mocking up happening right here

All back from coating and looking fresh! JT coating killed it on this one. Big thanks to them!

Everything is getting bolted up and it’s looking good. I’m really digging the wrinkle black powder coating on the compressor housing, intercooler pipes, and manifold. It keeps the car looking brand new and almost stock at first glance.

After getting finished up and tuned by Anthony, it made 388whp and 358wtq at 16 psi! This turbo set-up is capable of a good amount more, but we kept it safe due to the stock engine and clutch.

Here’s a dyno graph comparing the car when it was stock and after we finished up with the turbo kit and tune. You can see the massive difference in power. With our big tube UEL header, the 5858 Precision turbo hits full boost only 300 RPM past that of a stock STi. Having that much more exhaust flow played a huge role in making these kind of numbers that early in the RPM range. With a built engine and upgraded clutch, this kit will be ready to handle a bunch more power. A big thanks to Mike for bringing us this project, and we hope to see him and his STi back soon!

This build was getting buttoned up last week. The car made its way onto the dyno, and it was LOUD. The titanium hood exit makes this thing scream. A few things still needed to be buttoned up, but everything else was ready for engine break-in and tuning.

Once tuning was done, the last few details were finished up. The hood exit looks sweet with its burnt titanium trim on the hood. It’s definitely a cool touch. Attention to detail is a huge part of all of our builds, and it especially shows with this one.

The face of the WRX was put back on, and the car was sent on its way. That wraps up this build for now!

After getting all the nice powdercoated parts bolted up, the engine was bolted back up in the engine bay. The polished Cosworth intake manifold really tops off the look of everything.

Before the engine and trans were mated back together, we opened up the 5-speed for some modifications. It really is crazy how everything works inside a gearbox. So many tight tolerances and moving parts working in harmony.

This shaft on the tail of the gearbox is a spool that locks the center differential, enabling it to work as a RWD transmission. The front axles will be cut off at the hubs to inhibit the front wheels from turning. The hubs will be left in place so that everything stays securely bolted together. This car is riddled with WRX performance parts. Check out our parts web store for whatever you need. Up next is going to be a titanium hood exit exhaust!

This WRX hatch was awaiting the return of its EJ255. We went through everything on this engine: pistons, rods, cams, the works. Once it’s all buttoned up, it’ll hop over to our dyno for a tune. If you want the parts going into this EJ, give us a call or visit our Parts Web Store.

A fully built engine isn’t the only thing we’re working on. There’s a unique spin on this build, or lack there of. This Subaru is no longer going to spin the front wheels when we’re done with it. That’s right, a rear wheel drive conversion is in the works. The plan is to lay down somewhere in the ballpark of 400 rwhp on our dyno when all said and done. Check back for more updates!

Last week we had another Subaru in for a custom ECUflash tune. This time it was a ’02 WRX with a custom rotated turbo kit using a GReddy 18G turbocharger. With a unknown history 60k mile motor, and a host of other typical Subaru upgrades this is a classic do it yourself modified WRX. It’s a great feeling when you can help an owner finish his project by putting a solid tune on the car.

After fighting a few boost leak issues early on we were able to get back to tuning. Slowly turning up the boost the car was picking up power every pull. By 20psi it laid down 309whp on our Dynojet. The owner was extremely happy with it cracking the 300whp barrier & told us this car will have the most horsepower he’s ever driven or rode in. We felt 300whp was a good place to leave the car at for the owner to enjoy while working out a few other things on the setup.

Tons of big horsepower cars come in and out of the shop on a daily basis which can lead to expectations held high on every project/tune. This home built project making 300whp can show us all that even with “only 300whp” there is still people out there that enjoy chasing goals big and little. At the end of the day its the owner who will be driving the car day in and day out and if he’s happy nothing else matters.

Another new model STi came in for a tune the other day, and boy are the stock tunes dangerous. We have done multiple newer body Subarus and they always seem to run very lean & make disappointing power. After making a handful of adjustments this car went from a measly 220whp to 317whp. One of the best things about the tune is that its safe. We’ve seen to many Subarus come in blown up because of “off the shelf” tunes or people beating the cars hard without a tune. It is impressive that with only 3 power mods and a tune you can pick up 100whp!

Don’t hesitate to call us today to set up your tuning appointment! Thanks for watching.

We had a longtime customer bring this car in for a pre-purchase look over. After going over the car we found that it had low compression in one of the cylinders and was breaking up while going into boost. The customer purchased the car afterwards and brought it back in for a base tune so it could at least be driven smoothly & safely while a plan for a full build could be laid out.

Once on the dyno a small bit of tuning got the car running smooth and clean throughout the rpm range. Surprisingly even with the low compression at only 20psi it laid down just under 400whp & 380wtq! The owner was extremely happy with end result.

Knowing the engine has some issues & won’t last forever, the new owner is preparing to build it over the winter and possibly make a few changes to the turbo setup as well in hopes of bigger power. Check back in the future to see what route this car decides to take, but for now enjoy the sights and sounds of this 400whp widebody hawk-eye.

Here at PSI PROformance we have done a few recent 4-500whp rotated turbo kit Subarus with great results. Some customers just want more, and we are here to make it happen.

We have modified this STi a few different stages since the owner purchased it and after talks of wanting more power he decided on a 600hp goal.

The project began with our custom-spec built/sleeved engine, and our custom rotated turbo kit. With the power goals in mind, a Precision 6262 turbo & E-85 fuel were chosen to make it all come together. With a host of supporting mods & custom built parts done in-house the car easily put down 600 WHEEL horsepower after being tuned on our Dynojet.

We have since installed a resonator to our Race-spec exhaust and the car is happily in the hands of the owner. We are looking forward to it coming back in for a re-tune on higher boost when the owner is ready. At only 29psi the setup is not even breaking a sweat.

The customer brought the car back a week later to have us add a muffler as he was getting dirty looks from annoyed neighbors.

Please check us out on facebook to see regularly updates photos from around the shop including the build of this STi. If you have any questions regarding the build, or would like to start a Subaru build of your own please don’t hesitate to contact us at the shop. Our number is: 215-361-7100